#include<cstdio>
#include<cmath>
using namespace std;
int main()
{
double m,k;
scanf("%lf%lf",&m,&k);
printf("%.0lf",(1-pow(k,m))/(1-k));
return 0;
}
#include<cstdio>
#include<cmath>
using namespace std;
int main()
{
double m,k;
scanf("%lf%lf",&m,&k);
printf("%.0lf",(1-pow(k,m))/(1-k));
return 0;
}